Agilent Technologies 3070 Series, Подготовка площадки

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© Agilent Technologies 1989–2002 Agilent 3070 / 79000 Site Preparation 10-135
Chapter 10: Site Preparation – Power Requirements for Older Systems: Tester Power Requirements (Series I/II)
Sizing the Input Conductors and Circuit Breakers
To ensure adequate peak voltage for proper operation of
the system power supply, two minimum requirements
must be met:
■
A system drop must be connected to an ac source
with at least the minimum voltage.
■
The conductor used for the drop must be sized to
handle peak current loads with less than a
5-percent drop between the ac source and the
system.
Use Table 10-33 on page 10-136 and Table 10-34 on
page 10-137 to direct you to another table listing the
correct conductor sizes. Using a conductor that is too
small can cause a larger voltage drop across the system
drop. This could mean that the peak voltage into the
PDU is not sufficient for proper operation. If the ac
source provides more than the minimum voltage, then
the maximum voltage loss between the source and the
system is not as critical.
CAUTION
✸
All power configurations using a neutral are
unbalanced, so there will be neutral current.
Therefore, make the neutral conductor the same
size as the line conductors.
NOTE
The wire sizes recommended in this chapter are
for the SO cord from the receptacle to the system.
The electrician has the responsibility to size the
wire to the receptacle so that the voltage drop
from the transformer to the 3070 system does not
exceed 5-percent of the nominal voltage.